Your set of keys came, or should have come with a little metal plate with a number on it. That number if you know/remember it can be used to order keys from your dealer.
The chip needs to be programmed to match your car. Call your stealership for keys; sorry!
Search for replacement keys. Quite a few topics, including I think prices people had to pay.

Just bite the bullet and do it at the stealership, unless you want to take the time to order keys from different places, drive them around, cut them at one place and program them at another etc. You're gonna save yourself $25, spend $20 in gas and waste 4 hours haha.

The other thing about the generic ones from locksmiths that are not OEM toyota: they have a battery in the key, which I've heard bad reviews about. I would be completely annoyed to change the battery in my key every 6 months. when my watch battery goes dead... I get a new watch